Core grinding machine



Feb. 24, 1953 c. H. MILLER CORE GRINDING MACHINE 2 SHEETSSHEET 1 iled June 23, 1950 M \w\ IIII Feb. 24, 1953 Filed June 25, 1950 2 SHEETS--SHEET 2 1 .E. I; E

i INVENTQR. h I: C zdrrfrzce M/Zer W jg Patented Feb. 24, 1953 cons GRINDING MACHINE Clarence H. Miller, Detroit, Mich., assignor to Standard Pattern Works, Detroit, Mich., a corporation of Michigan Application June 23, 1950, Serial No. 169,865

4 Claims. (01. 51-131) This invention relates generally to machines for grinding sand cores or the 1ike,and more particularly to a novel core grinding machine incorporating means for disposing of the sand and silica dust ground from a core.

It is an object of this invention to provide a. core grinding machine in which the sand ground from a core is directed into an enclosed receptacle so that it may be reused,and so that it will not be thrown onto the working parts of the machine or into the atmosphere and adjacent areas of the machine. I

It is a still further object of this invention to provide a machine of the aforementioned type, in which the sand will be directed into a receptacle while the silica dust will be drawn by an exhaust blower from the sand and machine and deposited in a dust collector, or the like.

It is a still further object of this invention to provide, in a machine of the aforementioned type, novel mean for removing the sand from the receptacle in a simple, efiicient and economical manner.

It is a still further object of this invention to provide in a, machine of the aforementioned type, a rotatable turntable and a novel arrangement for supporting the same.

It is a still further object of this invention to provide a machine of the aforementionedtype which is rugged in construction, eflicient in operation, and in which the ground sand and silica dust will be positively and eificiently handled so as not to impair the operation of the machine or the health of the operator, and so a to enable the sand to be reused in the making of other cores.

These and other objects of this invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, in which: 7

Figure l is a side view, partially in section and partially in elevation, of the device of this invention;

The shaft I3.is connected with the turntable],

2 in any suitable manner, and a collar I5 prevents relative vertical movement between the turntable and shaft. Spaced bushings l I are disposed between the outer periphery of shaft I3 and the adjacent wall of the supporting structure 9 to provide bearing surfaces for the rotatable shaft and to maintain the shaft in its proper vertical position. A seal I8 is disposed in the upper end of the structure 9 and engages the shaft I3 to prevent the ingress of dirt or other foreign particles between the shaft and bushings. The lower end of the shaft I3 is recessed at I9 to receive the upper portion of a ball element 2 I. The lower end of the opening I I, in the base 5, is closed by mean of plate elements 23, which are secured to the base 5 by means of cap screws 25. A hardened metal insert 21 is disposed in a recess 29 in the upper face of the top plate member 23, and the ball 2| rests upon the insert 21 so that the turntable is supported by the insert 21 through the ball 2| and can rotate relative to the base 5 and it supporting structure 9 on the ball 2|. A ring gear 3| is connected to the turntable 1 adjacent the under side thereof, and meshes with a gear 33 of a speed reducer unit 35. A suitable motor 31 is connected with a speed reducer 35 for driving the work table 1,.if so desired. In

many cases with machines of this type the turntable is not positively driven by a motor, and in such case the speed reducer and motor may be eliminated and the turntable I merely rotatably supported on the base 5. In such cases the engagement of the rotating grinding wheel with the core will cause rotation of the table at a desired speed, and also as the grinding wheel rotates relatively slowly, such as 420 R. P. M., there is no need to clamp the core on the table.

A vertical column 39 is supported on the base 5 and extends upwardly therefrom rearwardly of the turntable l. The vertical column structure 33 includes a front wall 4I, back wall 43, side walls and a bottom wall 41. The vertical column 39 is hollow and supports, adjacent the upper end thereof, a housing or tool-supporting head 49. The housing 49 is mounted in suitable ways (not shown in detail) on the vertical column structure 39, and is adjustable forwardly and backwardly thereon by means of an operat- 51, one gear of which meshes with a gear rack 59 on the housing means o that when the handle or wheel Si is rotated the housing will be adjusted relative to the vertical column structure. A housing member 6| is connected in the front face of the housing 49, through ways 63, for movement in a vertical direction, and a suitable mechanism 65, including a hand wheel 61, screw 69, nut H and counterweight 13, is provided for adjusting the housingimember 'Bl vertically .relative to the housing 49. "A housing His connected with the front face of the housing 6|, and is adapted to contain a suitable motor or the like (not shown) for rotatably driving a grinding wheel 15 for grinding a sand core mounted on the turntable I, which is disposed below the grinding wheel 15. It will thus be seen that the grinding whee1 is carried by a suitable supporting structure for both horizontal and vertical adjustment on the vertical column supporting structure 39.

The front wall M of the vertical column 39 "is provided with-zanopening 'll therein adjacent to the table top -1 and the :back wall 43 of the column-39 is provided with an opening 19. The vertical column sii provides a receptacle into which sand groundfrom the core on the turntable -"i will-be directed, as will hereinafter appear. lihe upper portion "of the vertical column 39 :is closed by means of'a suitable closure .plate or the like:8i,s0 that sand cannotfiow upwardly into the gear train'fil and housing 49. .A filter closes the opening 19 in theback wall 4 3 "of the vertical column, and a bonnetor "enclosure encloses the filter 83 and is connected with the back wall of the vertical column. The bonnet 85 may be connected with the-vertical rcolumn 39in any suitable manner, and preferably is connected therewithso as to be detachabletherefrom. Ihe bonnet 85 supports the-filter 83 in the proper position to close the opening 1-9. exhaust blower -81 is provided adjacent the machine, which is driven :-by a suitable motor :85. The blower 87 is connected with the-bonnet :85 through suitable conduit 'neans 9 i and the blower is connected .at its outlet side "with a .dustcol- 'lector 95, which may be of 'anysuitabletype.

Whenthemachine is in operation so that a core supported 'on airot'atabie table 1 is being groundpthe exhaust blower 8'7 willcreate-adraft which willcause thesand and silica :dust ground from'thecore to flow through the opening 'li :i-n

theifr'ont wall'of the vertical column 3%, and will cause the silica dust to flow throughthe filter S3 and into "the-bonnet 85,, while thefilter will prevent the passage of the sand :thereth'rough so that the sand-will'drop down into 'theibot-tom of the vertical column. The "blower will draw the silica dust from thebonnet '85 through-the conduit 9!, and "discharge it into the "dust '"collector 95, so that it will not circulate into the atmosphere, so-as to affect the health =of-the operator of the machine, and-also so that'itds separated from the sand'and :thezsa-nd in .the vertical column receptacle will be cl'ean'iand reusable. ,In order to positively insure that the V sand or silica-dust will flow into "the vertical.

column, asheet metal 'cover-orclosurefl'i is pro- 'vided, which surrounds the portions'ofthe work table remote from the vertical columnopening H but which 'is, -ofcourse, suitably constructed soas not't'o interferewith movement-of thegrinding wheel -or positioning-of thecore .on the work table '.'-Ilhecover or closure :Sluissupported on the "base by suitable supporting structure'i99,"- and ammo element Jill :is disposed .be-

:lowtlr'e :iwork table "1, adjacent the wertical column, for directing any sand which falls from the table into the vertical column receptacle through an opening H33 in the wall 4!, below opening 17.

While the sand may be removed from the vertical column receptacle in many ways, such as by removing the bonnet and filter 83 and shovelling the sand from the receptacle, -a novel, simple and efiicient arrangement for removing the sand is illustrated, which includes a vertically extending pipe llll, the lower end of which is disposed adjacent the bottom 41 of the receptacle. Extending across the top of the pipe [0| and communicating therewith is a transversely extending conduit I83, one end of which is connected to a suitable high pressure air supply source I 05, and the opposite end of which is disposed adjacent a wheelbarrow IE1, or the like, positioned adjacent to the machine. The flow of air across the top of the pipe ID! will cause the sand to flow upwardly through the pipe till and be carried in the air stream to the wheelbarrow i, from whence it may be removedin any-conventional manner.

It will thus be seen that the "device of this in- ;vention ,providesa novel, positive and simple arrangement'for removing the silica dust from the sand and for removing the sand from the receptacle so that it may be reused. At the same time the sand and dust are preventedfrom fiowing into the area adjacent the machine, .oron the operating parts of the machine itself. .It will *aisobe appreciated that a novel and simple structure is provided for rotatably supporting the work table on which the core ismounted, .andth'ecentire Jmac hin'e provides a more efficient and .desirable arrangement for grindingsandcores and the like than any heretofore developed.

What is claimed is:

1. A machine for grinding sand cores of the type containing silica dust, including a-support- *ing base structure a work table rotatably supported on said base structure for supporting -a core to be-ground, structure forming -a hollow vertical column extending upwardly from said b'asestructure adjacent said work table, a housing, means supporting said housing for moveinent on the upper "portion of said vertical column, means connected with saidhousingfor supporting "a grinding wheel .in position for engagement with a core on "the 'work table, the wall portion of said vertical column adjacent said -worktable having an inlet opening thereinga "wall portion of said vertical column spaced from said first opening having an outlet "opening therein, said vertical column providing, between said openings, .a receptaclefor sand ground from said core, means closing the upper end of said vertical column above said openings to prevent sand from passing upwardly into said "housing,

filter means closing said outlet opening of "the type which will permit silica dust to pass therethrough and prevent sand from passing therethrough, and exhaust blower means connected with said receptacle openingsfor drawing sand aground iromacore through said first opening and into the receptacle and for drawingsilica dust through said filter 1means,,while the :sand

rernains in the receptacle.

:2. A-machine fcrgrinding sand cores :of the-type containing silica dust, including a supportingbase umn extending upwardly from said base structure adjacent said work table, a housing, means supporting said housing for movement on the upper portion of said vertical column, means connected with said housing for supporting a grinding wheel in position for engagement with a core on the work table, the wali portion of said vertical column adjacent said work table having an inlet opening therein, a wall portion of said vertical column spaced from said first opening having an outlet opening therein, said vertical column .providing, between said openings, a receptacle for sand ground from said core, means closing the upper end of said vertical column above said openlugs to prevent sand from passing upwardly into said housing, filter means closing said outlet opening of the type which will permit silica dust to pass therethrough and prevent sand from passing therethrough, and exhaust blower means connected with said receptacle openings for drawing sand ground from a core through said first opening and into "the receptacle and for drawing silica dust through said filter means, while the sand remains in the receptacle, and closure means connected with said supporting base structure and surrounding a portion of said work table remote from said receptacle first opening so as to prevent sand ground from a core from being thrown outwardly from said table away from said receptacle and into the atmosphere.

3. A machine for grinding sand cores of the type containing silica dust, includin a base supporting structure, a work table disposed above said base structure for supporting a core to be ground, means rotatably supporting said table on said base structure, structure forming a hollow vertical column supported on and extending upwardly from said base structure adjacent to and behind said Work table, housing means supported on said vertical column structure above said work table, means for adjusting said housing means relative to said vertical column including an operating handle connected with a shaft projectin through one side of said vertical column structure, structure mounted on said housing means for adjustably supporting a grinding wheel, said housing means and grinding wheel supporting structure being adjustable to position the grinding wheel for engagement with a core on the work table, the front wall of said vertical column structure adjacent said work table having an opening therein through which sand ground from said core may pass, the opposite wall of said vertical column structure having an opening therein, said vertical column structure between said openings and below said handle shaft providing a receptacle adapted to receive and sup-port ground sand, means closing the upper portion of said vertical colunm below said housing means, a filter closing said second opening and adapted to permit silica dust to pass therethrough but to prevent the passage of sand therethrough, bonnet means connected with said vertical column structure opposite wall and enclosing said filter, exhaust blower means connected with said bonnet means and adapted to draw sand ground from the core through said vertical column first opening and into the receptacle and-to draw the silica dust through the filter while the sand remains in the receptacle.

4. A machine for grinding sand cores of the type containing silica dust, including a base supporting structure, a work table disposed. above said base structure for supporting a core to be ground, means rotatably supporting said table on said base structure, structure forming a hollow vertical column supported on and extending upwardly from said base structure adjacent tc and behind said work table, housing means supported on said vertical column structure above said work table, means for adjusting said housing means relative to said vertical column including an oper ating handle connected with a shaft projecting through one side of said vertical column structure, structure mounted on said housing means for adjustably supporting a grinding wheel, said. housing means and grinding wheel supporting structure being adjustable to position the grinding wheel for engagement with a core on the work table, the front wall of said vertical column structure adjacent said work table having an opening therein through which sand ground from said core may pass, the opposite wall of said vertical column structure having an opening therein, said vertical column structure between said openings and be low said handle shaft providing a receptacle adapted to receive and support ground sand, means closing the upper portion of said vertical column below said housing means, a filter closing said second opening and adapted to permit silica dust to pass therethrough but to prevent the passage of sand thcrethrough, bonnet means connected with said vertical column structure opposite wall and enclosing said filter, exhaust blower means connected with said bonnet means and adapted to draw sand ground from the core through said vertical column first opening and into the receptacle and to draw the silica dust through the filter while the sand remains in the receptacle, a conduit supported in said receptacle and having its lower endadjacent the bottom of said receptacle, and means connected with the upper end of said conduit for withdrawing sand from said receptacle through said conduit.

CLARENCE H. MILLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 276,879 Randolph May 1, 1883 1,003,099 Freeman Sept. 12, 1911 1,262,529 Lowe Apr. 9, 1918 1,392,325 Hanson Oct. 4, 1921 1,424,713 Coburn Aug. 1., 1922 1,493,394 Leon May 6, 1924 1,528,439 Leiman Mar. 3, 1925 1,642,171 Reavis Sept, 13, 1927 1,986,378 Smith Jan. 1, 1935 2,216,693 Monroe Oct. 1, 1940 

